Analysis Capsizing of the Vessel Due to a mechanical failure aboard the Cape Jedsue, only the Cape Fin-Tose was able to harvest the mackerel. This resulted in a large set of fish being tightly pursed in the seine for several hours. Unable to swim, the mackerel started to die and, as they sank, their combined weight acting against the bottom of the net increased the loading on the net. This loading transferred to the seine head line lashed to the Cape Fin-Tose's starboard bulwark and to the Cape Jedsue's net roller on the main deck's starboard bulwark. This produced a large heeling moment on both vessels, but because the Cape Jedsue had not started loading, this vessel had sufficient stability and reserve freeboard that the effect was far less pronounced. As the heeling manifested itself very quickly, the crew of the Cape Fin-Tose was unable to completely release the head line and relieve the load on the bulwark. Furthermore, as the Cape Jedsue released the tension of the seine from the power block while manoeuvring to avoid the capsizing Cape Fin-Tose, more weight was transferred to the Cape Fin-Tose's bulwark, thereby exacerbating the situation. Although the total force exerted on the seine by the fish cannot be precisely calculated, it is estimated that some 18000-45000kg (40000-100000pounds) of mackerel remained in the seine, along with the weight of the seine itself. Therefore, a considerable tipping force (18- 45long tons) would have been acting on the bulwark of the Cape Fin-Tose and over the roller of the Cape Jedsue. Analysis shows that the transverse stability characteristics of the Cape Fin-Tose would be slightly reduced with, for example, an arbitrary force of 1long ton acting on the bulwark. This effect would markedly increase with a corresponding increase in force. In this occurrence, it would have only taken a threshold force of 6.5long tons acting on the bulwark to exceed the vessel's heeling moment. The capsizing was accelerated by downflooding through the open hatch and accommodation door, which occurred at about 45degrees of heel. It is also likely that some of the fish would have shifted in the hold prior to reaching that angle, further contributing to the capsizing. Stability Booklet Notes to Master Notes to Master 9C, which formed part of the Intact Trim and Stability Booklet for Capelin, Mackerel, and Herring, instructed that during seining, all trawling gear as well as the gantry are to be removed from the vessel. Although owner-initiated stability calculations for the Cape Fin-Tose were generated with the understanding that the term all trawling gear included both trawl winches and warps, this fact was not clearly stated; trawl winches and warps were not removed prior to departure for seining. Similarly, Note 4A, requiring that the lazarette fuel tanks be empty while seining, was not complied with. Such notes are produced to give the vessel operators guidance for safety and are recommended by Transport Canada in Ship Safety Bulletin 04/2006, pending the publication of the new Fishing Vessel Safety Regulations in 2009. Liferaft Although not required by regulation, the Cape Fin-Tose was fitted with an eight-person liferaft, complete with hydrostatic release mounted on the vessel's foredeck. Because the liferaft was susceptible to seas breaking over the bow, two composite lashings consisting of binding straps and crab twine were typically used to secure the raft to the cradle. When the vessel capsized completely, it is likely the hydrostatic release activated, but the liferaft may have been prevented from deploying because the residual buoyancy of the liferaft capsule was insufficient to part the crab twine. It is also possible that the liferaft, like the emergency position-indicating radio beacon, became trapped under the overturned vessel and was prevented from floating to the surface. If this happened, the liferaft capsule would have filled with seawater at some point during the two hours the vessel remained afloat and lost its residual buoyancy. When the vessel finally sank, the liferaft would have sunk as well. The vessel was not being operated in accordance with notes included in the (pending approval) stability booklet, in that both lazarette fuel oil tanks were not empty and the trawl winches and warps were still aboard. The inability of both vessels to harvest the mackerel from the seine simultaneously prolonged the length of time the fish were captured in the net and the fish likely died. When the mackerel in the net started to die, their deadweight acting on the bottom of the net increased the load on the vessel's starboard bulwark. The weight transfer as the Cape Jedsue released the tension on the seine net further increased the weight on the Cape Fin-Tose's bulwark. The heeling moment exceeded the righting moment and the Cape Fin-Tose capsized.Findings as to Causes and Contributing Factors The vessel was not being operated in accordance with notes included in the (pending approval) stability booklet, in that both lazarette fuel oil tanks were not empty and the trawl winches and warps were still aboard. The inability of both vessels to harvest the mackerel from the seine simultaneously prolonged the length of time the fish were captured in the net and the fish likely died. When the mackerel in the net started to die, their deadweight acting on the bottom of the net increased the load on the vessel's starboard bulwark. The weight transfer as the Cape Jedsue released the tension on the seine net further increased the weight on the Cape Fin-Tose's bulwark. The heeling moment exceeded the righting moment and the Cape Fin-Tose capsized. Although fitted with a hydrostatic release, the liferaft may have been prevented from deploying because it was secured to its cradle with two strap-type bindings. If it did release from its cradle, it probably became trapped underneath the overturned vessel. It is likely that the emergency position-indicating radio beacon, which was fitted with a hydrostatic release, released from its enclosure but became trapped underneath the vessel. The deployment and subsequent activation occurred immediately after the vessel sank. The speed at which the vessel capsized precluded the donning of lifejackets, the deployment of the liferaft, and issuing a distress call.Findings as to Risk Although fitted with a hydrostatic release, the liferaft may have been prevented from deploying because it was secured to its cradle with two strap-type bindings. If it did release from its cradle, it probably became trapped underneath the overturned vessel. It is likely that the emergency position-indicating radio beacon, which was fitted with a hydrostatic release, released from its enclosure but became trapped underneath the vessel. The deployment and subsequent activation occurred immediately after the vessel sank. The speed at which the vessel capsized precluded the donning of lifejackets, the deployment of the liferaft, and issuing a distress call. Despite the fact that there was no regulatory requirement to do so, the owner had an inclining experiment carried out. Stability data was produced and presented to Transport Canada for approval. The requirement, based on the stability book Note to Master, that all trawling gear was to be removed when seining, did not clearly indicate that the trawl winches and warps should also be removed.Other Findings Despite the fact that there was no regulatory requirement to do so, the owner had an inclining experiment carried out. Stability data was produced and presented to Transport Canada for approval. The requirement, based on the stability book Note to Master, that all trawling gear was to be removed when seining, did not clearly indicate that the trawl winches and warps should also be removed.